1. Field of the Invention
This invention relates to livestock handling equipment and more particularly to a squeeze chute for selectively immobilizing an animal in a standing position to allow any number of operations to be safely performed on the animal.
2. Description of the Related Art
In livestock operations it is often necessary to restrain the animals for palpating, immunizing, branding, treating, weighing, loading, etc. Corrals, loading chutes, alleyways, pens, and the like, have heretofore been constructed and employed by livestock operators and veterinarians for these purposes. These structures are often constructed permanently from materials such as stone, barbed wire, wooden rails, steel pipe, and the like. However the capital investment required for such permanent structures is often prohibitive to ranchers having small operations, particularly those that operate their livestock on small isolated tracts of grazing land. Furthermore, many such ranchers lease, rather than own, their grazing land and naturally wish to avoid making permanent, fixed improvements.
A common solution to this problem is to physically transport the livestock to a remote location having the necessary equipment. However, transporting a herd of large animals tends to be relatively time-consuming and expensive. A round trip from the grazing pasture to a treatment facility requires loading, transporting, and unloading the animals twice. Naturally, the time and expense associated with transporting livestock increases with the distances and number of animals involved.
A disadvantage with many prior art portable animal handling devices is that large animals can be hazardous to workers trying to direct and control them with such equipment. Animals that are unaccustomed to confinement frequently balk at entering confining structures and may even panic. After being restrained, an animal may then suddenly begin kicking or attempt to climb up or back out of the chute. Many of the prior art animal-working structures provide little or no protection from such hazards.
Squeeze chutes can be provided with hydraulic power systems for opening and closing their gates and constricting and expanding their sidewalls to reduce or expand the size of the enclosure in which animals are received. Hydraulic power systems have the advantage of permitting control of the operable components from a single control station. However, these control systems are typically located in a fixed position at one end of the squeeze chute. This can limit the operators view of the work being performed on the animal and typically limits the placement of the squeeze chute with respect to permanent structures located nearby.
Prior to the invention disclosed in assignee's prior U.S. Pat. No. 6,609,480, the prior art squeeze chutes were usually provided with sides that pivot inwardly in order to squeeze livestock. Since the distance between the sides at the bottom must conform substantially to the width of the animal, this type of chute requires adjustment in the spacing of the sides if both large and small animals are to be handled. It is also difficult for large animals to enter or be driven into the chute because its width at the bottom is barely sufficient to accommodate the animal. In addition, the manner in which the sides pivot tends to shock or excite the animal and often causes the animal to lose its balance. The construction of the sides of existing squeeze chutes presents an additional problem in that the sides obstruct access to much of the animal's body, making examination and other operations on the animal difficult.
Another problem with many prior art squeeze chutes, prior to the invention disclosed in U.S. Pat. No. 6,609,480, relates to the operation of their gates. Squeeze chute gates often include a pair of panels, which are pivotally mounted on the squeeze chute frame so that they traverse arcs when they are moved between their open and closed positions. This motion tends to swing the panels into the faces of the animals, contributing to the animal's stress and sense of distress.
During particular treatment operations, the head of the animal must be firmly held in place to avoid injury to both the animal and the operator. For example, the application of ear tags, implants or other medicaments in the animal's ear is accomplished more safely if the animal's head is substantially immobilized. The same is true during the examination of the animal's eyes, ears and teeth. It is further preferred that the animal's neck be fully exposed and nearly motionless when taking blood samples from or making injections of any kind of serum into the animal's neck.
The methods of substantially immobilizing the animal's head, prior to U.S. Pat. No. 6,609,480, all require substantial physical effort by the operator. Nearly all of those methods include use of a stanchion either fixed or formed as a part of a portable chute such as those used for de-horning. The animal is held in the stanchion to keep its body confined. Then, a tray or platform may be placed under the animal's head, which is pressed against the tray to hold it in place. An alternative prior art method uses fixed length arms, which extend outwardly from the stanchion gate. These arms are typically not adjustable and generally need to be used in combination with a nose ring and rope. If the animal becomes excited when this method is used, it is necessary for the operator to hold the head until the nose ring can be inserted and the rope tied before the desired operation can be carried out.
Prior art squeeze chute designs, prior to U.S. Pat. No. 6,609,480, typically limit the operator's ability to safely enter the rearward end of the chute, behind the animal, without compromising the physical restraint of the animal. Furthermore, such prior art designs are incapable of selectively immobilizing the animal's hip area without increasing the transverse squeeze pressure exerted by the opposing sidewalls. Accordingly, even if the operator is able to enter the chute behind the animal, simple animal husbandry operations are made difficult if not dangerous.
As the animals are worked, some may have a tendency to lie down or even collapse under the surrounding conditions. Prior art squeeze chutes, prior to U.S. Pat. No. 6,609,480, typically do not provide for a method of selectively and adjustably supporting the animal's abdomen. This not only increases the difficulty of working the animal but compromises the safety of the animal.
The squeeze chute of assignee's prior U.S. Pat. No. 6,609,480 solved a majority, if not all, the problems associated with squeeze chutes. The instant invention is regarded as a significant improvement over assignee's earlier squeeze chute in that the noise associated with squeeze chutes has been greatly reduced in the present invention. The instant invention reduces much of the metal to metal contact of moving parts thereby decreasing the noise associated therewith while providing an increase in the durability of the squeeze chute. The operation of the instant squeeze chute is extremely smooth and quick.